Temporal stability of the Brief Symptom Inventory 18 among Irish college students over four weeks

Of the currently limited available data on the mental health of students in Ireland the most notable are provided in the College Lifestyle and Attitudinal National (CLAN) Survey (Hope, Dring, & Dring, 2005). Recently, Houghton et al. (2012) found among students at an Irish university that women reported significantly higher levels of symptomatology than men on each of the three 6-item subscales of the Brief Symptom Inventory 18 (BSI 18; Derogatis, 2001) (anxiety, depression, and somatization) and the Global Severity Index (GSI; summed total of the 18 items). Similarly, final-year students had significantly worse mental health than non-final-year students. Internal reliability, construct validity, and factor structure of the BSI 18, were reported but no data on the test-retest reliability of the measure. Our aim was to supplement these findings by reporting on the test-retest reliability of the BSI 18 in a small sample of Irish college students. On two occasions, separated by four weeks, 28 Irish college students completed the BSI 18. Satisfactory levels of internal reliability (>.7; Cronbach's α) were found for the depression (Time 1 α =.76, Time 2 α =.70), and anxiety (Time 1 α =.82, Time 2 α =.75) subscales, and the GSI (Time 1 α =.87, Time 2 α =.86), with the exception being somatization (Time 1 α =.52, Time 2 α =.76). At both administrations, scores on each measure were highly associated (somatization r =.50, p <.01; depression r =.44, p <.05; anxiety r =.59, p <.001; GSI r =.52, p <.001) and no significant difference in scores was found (somatization Time 1 M = 3.92 (2.69), Time 2 M = 3.55 (3.60), t =.57, p >.05; depression Time 1 M = 2.93 (2.89), Time 2 M = 2.89 (3.13), t =.06, p >.05; anxiety Time 1 M = 3.79 (4.24), Time 2 M = 3.25 (3.23), t =.87, p >.05; GSI Time 1 M = 10.64 (8.59), Time 2 M = 9.68 (8.40), t =.60, p >.05). These data provide evidence for the internal reliability and temporal stability of the three subscales of the BSI 18 (anxiety, depression, and somatization) and the GSI over a 4-week period among a sample of Irish college students. These findings are in line with those reported across a range of samples and countries (e.g., Andreu et al., 2008; Coutinho, Ferreirinha, & Ribeiro, 2010). Although the generalizability of these findings is limited owing to the small sample size, the selectivity of the sample (i.e., college students, mainly women), and the small length of the testing period (i.e., four weeks), the BSI 18 was found to be temporally stable. These findings also provide additional psychometric evidence that attests to the reliability of the measures within Ireland. The BSI 18 can be commended as a tool for further research among college students in Ireland.